[tex] \bf slope = m = \cfrac{rise}{run} \implies
\cfrac{ f(x_2) - f(x_1)}{ x_2 - x_1}\impliedby
\begin{array}{llll}
average~rate\\
of~change
\end{array}\\\\
-------------------------------\\\\
d(t)= 16t^2 \qquad
\begin{cases}
t_1=2\\
t_2=5
\end{cases}\implies \cfrac{d(5)-d(2)}{5-2}\implies \cfrac{400-64}{5-2}
\\\\\\
\cfrac{336}{3}\implies 112 [/tex]
what does 112 ?
well, it means that from the 2nd second to the 5th second, on average the ball was dropping at an average of 112 feet per second.
